Digital video files may include a large number of individual image frames. Manually sorting or retrieving specific image frames may be an overwhelming task for a user. Thus, indexing mechanisms have been developed to automatically mark, group, or catalogue image frames for users to search, browse, and sort frames with greater ease.
A number of representative or index frames may be extracted or generated from a video file. Each index frame may represent one or more (typically several) consecutive similar image frames, such as a video clip, act, or scene. Index frames may be extracted or generated based on the amount of change between consecutive frames in the video files.
One mechanism for determining the amount of change between frames is the local binary pattern (LBP) system. The LBP assigns numbers individually to each pixel in each frame. The pixel numbering for each pixel may indicate a pattern of surrounding pixels corresponding to histogram values thereof. If the difference in the numberings of corresponding pixels of each of a group of frames is less than a predetermined threshold, one of the frames may be extracted as an index frame, representative of the group. The LBP may compare each pixel numberings for corresponding pixels in each frame of the group of frames. Thus, a huge amount of numbers (e.g., equal to the number of pixels in a frame) may be compared to determine differences between frames. This individual pixel by pixel comparison may be a computationally intensive task.
Additionally, technological advances in image or video capture and storage techniques have resulted in an increased amount of image data for video files. Thus, standard mechanisms, such as the LBP, may require further computational effort to differentiate images for indexing video files.
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